Technical Working Group on Angat Reservoir Operation and Management
National Water Resources Board
July 30, 2015
WATER SECTOR PREPARES FOR EL NIÑO MITIGATION
Quezon City - Metro Manila water users are encouraged to use water wisely in preparation for the effects of stronger El Niño in the last quarter of the year up to the first months of 2016. Though heavy rains are intermittently experienced in the metro, these may only last until September according to PAGASA.
El Niño Impacts and Preparation
PAGASA announced that El Niño will intensify from moderate in the 3rd quarter to strong in the last three months of 2015. Below normal rainfall is also expected to affect most areas in the country. Despite the given scenario, concerns for water scarcity are still unlikely at the moment. The reduced water allocation from Angat Dam to municipal use is a form of management and preparation to mitigate negative effects of stronger El Niño in the 4th quarter of the current year and assure the availability of water until summer of 2016.
Onset of Rains
PAGASA officially announced on June 23 that the rainy season has begun and that 11-16 tropical cyclones (TCs), possibly “very strong”, are expected to enter the Philippine Area of Responsibility (PAR) from July to December. It is also forecasted that intermittent rains and thunderstorms with southwest wind will affect Metro Manila.
The expected rains will improve the situation of water level in Angat Dam. As of July 29 (12:00 m.n.), the water level from Angat Dam is 180.74 meters. This figure is still 29.26 meters short of the normal high water level (NHWL) of 210 meters.
The Technical Working Group on Angat Reservoir Operation and Management (TWGAROM) comprised of NWRB, MWSS, Manila Water, Maynilad, NIA, PAGASA, NAPOCOR and Angat Hydropower Corporation (AHC) hopes for sufficient rainfall until September to reach a manageable water level of Angat Dam to sustain enough water supply in October to December up to early 2016 even with intensified El Niño.
Effect of Reduction to Domestic and Irrigation Use
NWRB assures the Metro Manila consumers of continuous water supply at this point.
Starting July 1, 2015, the approved water allocation for domestic and municipal use is forty one (41) cubic meters per second (cms), a reduction of two (2) cms from June. This allocation continues in August even with the slight ascent of water because the level is still considered as low.
NWRB’s move to reduce the water allocation for domestic consumption will not affect the supply for Metro Manila. This step is a strategy to conserve water and reduce the water level decline in Angat reservoir while the country awaits for more rains this quarter as declared by PAGASA.
Based on historical statistics, the water level of Angat Dam on July 29, 2014 is 170.65 meters. This number is over ten (10) meters lower than the current level of the reservoir (180.74 meters) as of 12:00 m.n. The water allocation for domestic use is also pegged at 41 cms last year.
Given the situation in 2014, no reports of water interruption from water users in the metro were received.
As to irrigation, the allocation remains zero (0) cms in August. The provinces of Bulacan and Pampanga mainly depend on rainfall to water their agricultural lands. Once the monsoon rains stop, further coordination among the members of the Technical Working Group on Angat Reservoir Operation and Management will discuss the allocation for irrigation. The reservoir supplies water to Bustos Dam which in turn distributes water to about 27,000 hectares of farmlands in both provinces.
The water sector is ready for contingency plans in preparation for the possible impacts of the El Niño phenomenon.
Concessionaires are ensuring that their facilities are in good operating condition to avoid downtime. More water reservoirs have also been constructed particularly in elevated areas. Standby facilities for supply augmentation such as deep wells are also being prepared and will be operated when needed.
Farmers are being readied by NIA. Strategies to mitigate the effects of drought or dry season are cascaded to the Irrigators Associations including modification of cropping calendar and pattern as well as repairing of damaged irrigation canals and control structures, among others.
Though the agencies in the water sector are doing its best to address the needs of the areas supplied by Angat Dam, the public is constantly reminded to conserve and use water efficiently.